So I was having a conversation with someone earlier today about how the AFC East is the worst division in the league (I still stand by the opinion that the AFC South / NFC West is) in the last 20 years... So I looked up a lot of stats and this is what I found:
Bills - .438% Since 1999. (7/20 Winning Seasons)
Jets - .465% Since 1999. (This one is actually misleading since the Jets had a winning season 12/20 years (if you count 8-8 records like I do))
Dolphins - .478 Since 1999. (Dolphins surprisingly had less winning seasons than the Jets, at 10/20)
Patriots - .728 Since 1999. (19/20 Winning Seasons (the outlier being 2002, at 5-11))
Now let's do the AFC South:
Tennessee Titans - .513% Since 1999. (12/20 Winning Seasons, like the Jets)
Houston Texans - .484% Since 2002. (9/16 Winning Seasons, which if divided is closest to the Jets and Titans in terms of winning season %)
Indianapolis Colts - .634% Since 1999. (17/20 Winning Seasons)
Jacksonville Jaguars - .421% Since 1999. (7/20 Winning Seasons, like the Bills)
AFC West:
San Diego/LA Chargers - .516 Since 1999. (14/20 Winning Seasons)
Kansas City Chiefs - .509 Since 1999. (11/20 Winning Seasons, less than the Jets and Titans)
Denver Broncos - .540% Since 1999. (15/20 Winning Seasons, more than the Chargers)
Oakland Raiders - .394% Since 1999. (7/20 Winning Seasons, equaling the Jaguars and Bills)
AFC North:
Pittsburgh Steelers - .594% Since 1999. (18/20 Winning Seasons)
Cleveland Browns - .296% Since 1999. (2/20 Winning Seasons)
Baltimore Ravens - .575% Since 1999. (16/20 Winning Seasons)
Cincinnati Bengals - .460% Since 1999. (10/20 Winning Seasons, like the Dolphins)
AFC Winning % Since 1999 (Adding up each team average over the last 20 years and dividing by 16 teams): .503%
NFC East:
Dallas Cowboys - .525% Since 1999. (14/20 Winning Seasons, equal to the Chargers)
New York Giants - .503% Since 1999. (10/20 Winning Seasons, Bengals + Chargers)
Philadelphia Eagles - .572 Since 1999. (15/20 Winning Seasons, Like the Broncos)
Washington Redskins - .570 Since 1999. (9/20 Winning Seasons)
NFC South:
Atlanta Falcons - .506% Since 1999. (11/20 Winning Seasons, like the Chiefs)
Carolina Panthers - .563% Since 1999. (9/20 Winning Seasons, Like the Redskins)
New Orleans Saints - .540% Since 1999. (12/20 Winning Seasons, Jets + Titans)
Tampa Bay Buccaneers - .444 Since 1999. (9/20 Winning Seasons, Like the Redskins)
NFC West:
Arizona Cardinals - .431% Since 1999. (8/20 Winning Seasons)
St. Louis / LA Rams - .463% Since 1999. (8/20 Winning Seasons)
San Francisco 49ers - .434% Since 1999. (7/20 Winning Seasons, Bills+Jaguars+Raiders)
Seattle Seahawks - .531% Since 1999. (14/20 Winning Seasons, Cowboys + Chargers)
NFC North:
Chicago Bears - .484% Since 1999. (9/10 Winning Seasons, Panthers + Redskins)
Detroit Lions - .372% Since 1999. (6/20 Winning Seasons)
Minnesota Vikings - .516 Since 1999. (13/20 Winning Seasons)
Green Bay Packers - .600% Since 1999. (16/20 Winning Seasons, like the Baltimore Ravens)
NFC Winning % Since 1999: .503%
Some seriously interesting stuff to glean from this here.